package Demo;

public class Demo05 {
    private static Demo05 instance = null;
    private Demo05() {}
    public static Demo05 getInstance() {
        if (instance == null) {
            synchronized (instance) {
                if (instance == null) {
                    instance = new Demo05();
                }
            }
        }
        return instance;
    }

    public static void main(String[] args) {

    }



}
